The Yezdi Diaries: October 2007

Let's start you on a journey into your own inner space. Since time has no meaning to forever bikes, let's go to the source of the magic:
How2:Jawa353Engine.Part1:

Start by removing all the things that are likely to get in your way to the engine. On the Jawa, this means removing all the copious petticoats that this lady is enshrouded in.
Remove the obvious seat and spark plug lead. Leave the plug in since it'll keep foreign particles from getting into the engine. Imagine the effect of iron particles or fillings that might strip off nuts or other metal parts getting into your engine — instant abrasion and wear that is unnatural. So do your bike a favour and plug all openings that might allow dirt to get into it with wads of cloth. This philosophy extends to long-term storage as well; as Fatty or Chef Vivek, of Yamaha RD350 acumen advised me years back. Plugging the silencers with cloth ensures that the entire engine is sealed or blocked to any harm from the outside world.

Next, remove the air filter or air filter connection, depending on how old is your Jawa, and unscrew the threaded top cover of the carburettor. Remove the slide from inside the carb, taking great pains not to bend the long brass needle extending from below the slide. Wrap in soft cloth and put the slide end into a grocery plastic bag, alongside, unscrew the two screws holding the throttle grip to the end of the right handlebar. In case of the internally cabled throttle slide, remove the single screw holding the metal plug at the end of the slide grip. Slip off the throttle grip, dismantle and disengage the ball end of the throttle cable from the grip. Keep aside safely till re-assembly.

Don't stop here, start removing the carb itself. The older ones have a circlip that can be loosened by using a screwdriver, newer Jawas have threaded studs extending from the back of the cylinder, on either side of the carb inlet opening.

Studs, for the newbies, are like bolts that don't have a head on one end. Instead they have threads on both ends, enabling them to be screwed (ahem) from both ends. Told you, old ladies don't like studs, be they in the inlet or exhaust ends. However studs are used because they are better than bolts, so try and not substitute these with bolts if they break or worse, break off inside the hole. Any Yezdi/Jawa road warrior will tell you about stud troubles. Newbies can stop grinning at this point and go look up how to use a lock-nut on a stud. You will need to know when you face these inevitable troubles.

Having thus warmed up, you can start working on removing the side skirts. Open the nuts on the right side, holding the centre cowling to the brake lever, and the nut holding the brake lever to the two-piece front foot peg. Remember to loosen or open up the brake retainer from the wheel hub end, or else you would not be able to remove things without a potentially damaging struggle. Dunno about you, but I enjoy the activity and take every opportunity to sit back and stare at the bike. Things automatically come to mind and like a rock climber studying the cliff face for hand and foot holds, soon you will be able to chart a course in terms what you must do in order to do what you want to do, etc. In short, take time out to figure out your procedure, or regret it when you get stuck or must pay the price. Sun Tzu said, "Much computation brings triumph; little computation brings defeat."

Move on to the rear foot peg on the same side, and remove the bolt holding the side cowling panel to the rear foot peg support rod. You might not need to remove both nuts at the rear foot peg, as the side cowling is just attached to one of the two bolts. Move up to the point where the tank ends, remove the long bolt that holds the rear of the tank and the side cowling to the frame.

I hope you are keeping all the bolts you remove safely. There is no ego loss in writing them down in the order you remove them, I have spent up to 3 hours on two shock absorber bolts that won't go into place because over the years, they have worn or warped according to their location. So be careful, old ladies are cranky about you not putting things back where you took them from!

Another good idea is to simply replace them where they came from, after you remove the part they were holding in place. Provided, of course, that they won't get in the way of future steps in the procedure. Keep computing as you go along, lads. There is no substitute for a thoughtful mech.

Remove the two bolts holding the bottom edge of the side cowling from the other side (gear lever side) of the bike. Open the left side compartment (it's the bigger one that has been designed to accommodate the battery) and remove the three bolts holding the compartment in place. These three bolts can be replaced into their threaded holes on the rear foot peg support rod (two bolts) and the remaining one in the hole on the metal strip extending perpendicularly outwards from the main frame tube behind the engine. If you had been computing what you see, you would have figured this bit out by yourself.

Why open the left side specifically? Well, because that's what it says in the Jawa 353 workshop manual. Engines to be removed and mounted onto the frame from the left hand side of the bike. Good enough for me, I personally wouldn't even want to know what goes wrong any other way; too expensive in terms of possibility.

Coming to the chain, a longish and messy business if you don't mean business. It is always a good idea to slacken the chain slightly by loosening the rear axle and the chain adjuster nuts at the rear axle-shock absorber joint. Look up your owner's manual (now available online somewhere else, I'm sure) for which are chain adjusters. Remove the right hand side engine cover, so that you can see the chain on the front sprocket. Just behind the triangular 'samosa' shaped clutch mechanism. Just follow the clutch cable where it comes into the engine, and you will find your 'samosa.'

Put the bike into neutral and turn the wheel, watching the chain for the link which has the chain lock on it. It's actually quite simple, just use a large screwdriver's flat head to push the 'U' shaped clip/lock on the side of the link facing you. That is the way it is always assembled, with the chain lock clip outwards, and that is exactly how you will replace it later. Removing the clip enables the flat figure-of-eight shaped side piece of the link to come off the link. Just remove the other figure-of-eight shaped piece with the two straight bits sticking out of it from the other side of the chain, and it's in your hand.

Now go to the rear end of the chain guard and remove the single bolt and nut holding the two halves of the chain guard together. Remove both chain and chain cover for washing and re-greasing. A good idea is to fish out a small plastic bag, and put the greasy chain into it. This will keep it clean, and the surroundings and you as well.

Now for removing the exhaust bent pipes that connect the cylinder and the silencers. If you are one of the lucky ones with an original Jawa toolkit, you will find the requisite spanners to open the 'flower' shaped bent pipe retainers at the cylinder end. You can, in a pinch, cover the head of a large screwdriver with a doubled up piece of tyre tube to absorb shocks, and lightly tap the base of the 'petals' of the retainer. Take care, you are not allowed to break the petals just because you were too blind to see they were rusted or jammed and could be easily opened tomorrow after spraying some WD-40 (approx 130-180 rupees for a small spray can). So go lighter, rather than harder and you shall not damage anything.

Twist the bent pipes outwards and down, to remove them from the silencers. Notice the copper-looking ring that fits over the end that goes into the cylinder; you will have to replace these. It is a good idea to check inside the darkness of the pipes themselves to see how much carbon deposit has formed, as it can eventually constrict the 'breathing' of the engine, if not dislodged. Well, dislodged periodically, actually.

Two-strokes are by nature, prone to more carbon formation. It's in their blood, er, petrol-oil mixture, actually. Some of it can be got at with a long screwdriver, or with an old bike chain being dragged back and forth inside the pipe, or just consult any local mech for the messy jobs.

Speaking of messy jobs, it's time to get down on your hands and knees and locate the gearbox oil draining bolt under the engine. Get a container under it, and open slowly, taking care not to drop the bloody thing into the container itself — it's been known to happen. Stay in that position till you are sure the oil has drained, and oh yes! make sure you use a container that can hold at least a litre or you shall have to mop the floor too. Rock the bike slightly on the stand slightly from side to side or forwards and backwards in order to drain as much oil out as you can.

Step back and ask yourself if all you need to do next is remove the main (sometimes called 'foundation') bolts that actually hold the engine in place. Proceed towards the engine mounting bolts with two spanners or one spanner and a ratchet, or whatever, You still have to anchor one end of the bolt while opening the other. I, personally have replaced the nuts here with lock nuts. Those are the ones which have a nylon collar or ring inset into the threads at one end. The nylon holds on to the bolt threads for dear life.

Leave the uppermost bolts at the front and back for last. Make sure you are removing the engine from the frame from the left side of the bike. Jawa engines are asymmetric in shape and the side with the chain is longer at the back than the left side one which houses the clutch and electrics, that's why. But then, if you have been looking at the engine, you oughta have noticed it by now...and perhaps imagined that the engine is heavy, also likely to be slippery with oil/grease/dirt, therefore difficult to hold. I use work gloves and a nice wide stance, so as not to crush a vertebrae or something due to bad posture, get a nice grip on both sides and lift it straight down onto the cloth/mat placed there earlier by me, to provide a soft landing pad.

The rest of the operation can almost literally happen on your laptop. Or you could lock yourself in your bed room with lots of newspaper spread out on the floor.

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